Problem: If $x \diamond y = 3x-3y$ and $x \dagger y = x-4y$, find $-1 \dagger (2 \diamond -1)$.
First, find $2 \diamond -1$ $ 2 \diamond -1 = (3)(2)-(3)(-1)$ $ \hphantom{2 \diamond -1} = 9$ Now, find $-1 \dagger 9$ $ -1 \dagger 9 = -1-(4)(9)$ $ \hphantom{-1 \dagger 9} = -37$.